Flotation of ores.



UNITED STATES PA ENT OFFICE.

RAYMOND r. Bacon, or PITTSBURGH, PnN'nsYLvANIA. ASSIGNGR 'ro MIi'rALs RECOVERY COMPANY, on NEW YORK, N. Y., A oonrona'rlon or MAINE.

FLOTATIUN GI! ORES.

In Drawing.

To all whom it may concern Belt known that I, RAYMOND l BACON, a citizen of the United States, residing at Pittsburgh, Allegheny county, State of Pennsylvania, have invented certain new and useful Improvements in li lotation of Ores; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to, the concentration of ores, and toothe separationoi': metal. constituents thereof from each other and from associated gahgue, by a procedure which involves atwiractional separation of the metal constituents by combiner. solution and sulfidation and by subsequent flotation treatment.

The common flotation processes of concentrating low grade sulfid ores involve the indiscrimlnate separation of sulfide from gangue. Where the sulfid particles are themselves superficially oxidized or coated with an oxid film, it has been common prac ties to efiect the flotation in the presence of an acid which will dissolve and thus remove such onid films andleave the sulfid particles suitable for flotation. Metal constituents thus dissolved are, however, lost, so far as the flotation procedure is concerned, and they can only be recovered by a subsequent treatment. The dilution of such solutions I would often make recovery of the metal values therefrom. impracticable.

It has heretofore been proposed to convert oxid ores into sulfide by treatment with hydrogen sulfid or soluble su-lfids and by thereafter subjecting the ore to flotation; but such procedures also commonly involve an indiscriminate separation of all su'lfids formed from the gangue. Wherethe oxid or other non-sulfid constituents are present intimately blended with each other and with the gangue, the sulfidized ore retains the ore constituents in a similar or corresponding state of combination.

'It has further been proposed to separate oxidized lead and zinccompounds in suspen sion in the presence of an acid by treatment with sulfur'eted hydrogen or a soluble sulfid, thereby coating" only the lead witha' layer of sulfid without converting the oxidicefd the sulfid in an acid solution. The

zinc into sulfid, the zinc oxid not being Specification of Letters latent.

Patented Aug. '7, 1917.

Application filed. J 1111118413 4, 1916 Serial No. 70.185.

thus partially .sulfidized ore is subsequently subjected to flotation to recover the lead sulfid and leave the zinc behind in the pulp. With many ores such a proposal isnot practicable because of the intimate blending of the lead and zinc with each other and with the ganguc, even in a finely crushed condi tion. Where the lead and zinc are thus blended, the particles will remain physically combined even after partial sulfidation, so that a clear separation will be thus precluded. y

The various rocedures referred to above involve a pre iminary crushing to effect physical separation of thc' gangue from the ore.- Where the ores are of such a nature that such physical separation cannot be effected by crushing, the separation is to that extent prevented or prejudiced. the proposals to effect selective separation of different sulfid constituents from each other or from oxidized constituents are subject to the limitation that where these constituents are intimately ccnnbined together in the same finely divided, particles, their separation is not practicable for the reason that the treated particles will still retain such constituents in a similar or correspondmg state of combination.

[he present invention relates to an improved method of effecting a selective or fractional separation and concentration of oxidized and other ores in a simple and improved manner, whereby the disadvantages of prior proposals such as those referred to above are largely overcome or minimizedl As distinguished from indiscriminate separations ofsulfid constituents from gan e,

the process of the present invention invo ves a selective or fractional separation of etal constituents from each other which wi be more clear and sharp, and which can be applied to ores incapable of satisfactory oxidized or otherores containing metal'mn st1tu'ents forming acid solubleahd midi Similarly,

soluble sulfids are treated with hydrogen sulfid or other soluble sulfid in the presence of a sulficient excess of acid to sheet solution of the metal constituents formin acid soluble sulfide, whereby only the meta constituents aresulfidized which form acid in soluble sulfids. Thereby, the fractional sub fidatio'n and solution is simultaneously cf 'fected," the acid dissolving certain metal constituents, and the sulfid convertin other metal iconstituentsinto sulfids, so t at, at the end of the process, the acid soluble metal constituents will be in solution,'and the metal constituents forming acid insolublesulfids will be converted, partially or completely, into sulfids. Furthermore, the

disintegrating action of the acid in dissolvingthe acid soluble constituents tends i to exert a further disintegratin action u on' the oreparticles, sup lementa to the isw integrating action of t e preliminary crushof the ore.

in p ,v %he ores tobe treated may beeither of a sulfid or of an oxid or other non-sulfid nature, since the process isof more or less general applicatlon to ores contami metal constituents which are soluble in acids and form acid soluble sulfids and which also contain metal constituents forming insoluble sulfids. Where the ores are of anoxidized nature they can be treated according to the present invention after they have been preliminarily crushed: or otherwise finely 'divided to effect more or less complete separa-- tion of the metal particles from the gauges.

In treating sulfid ores it may be necessary or advantageous to subject the ore to a partial or complete preliminaryroast in order ore particles.

to thereby disintegrate the ore and convert the ore constituents into a form better adapted to .the subsequent fractional separation. ,Thus, .with zinc blend ores containing lead, the-lead and zinc sulfids may be so intimately combined and'blended with each other that it'is-impossible to efiect a physical separation by'anycrushing pro-. cedure. This combination may .even be so intimate that, u on treating with an acid and with the so uble sulfid simultaneously, the insoluble blend sulfid may prevent solution of the zinc. from the oxidation of the In such cases, it may be necessary to disintegrate the ore by a preliminary roast in order to. facilitate extraction I ,can proceed in: a more advantageous manby the acid of the zinc or other acid soluble constituents formin acid soluble. sulfids, at the same time that the soluble sulfid converts orcompletes the conversion of-the lead into "leadsulfid. a v

-After a preliminary roast the zinc will bemore readily extracted so that the combined extraction andmsulfidation operation ncr. So also, where the zinc sulfid is presentin sulfid oresin a formsuch that it can be dime dissolved in the presence of the soluble s d, the preliminary roasting may not be. 1:7 in order to obtain an eflective separoh. In all cases, however, the acid pmsent should be of a suflicient amount and of a suitable f gth to insure solut on of thedesiredmetal constituents formmg acid soluble sulfide so that these metal constituehts will be dissolved and held in solution at the same time that the soluble sullid present is efiecting the sulfidation. It will of course be understood, however, that the sulfidizing reaction may be completed before the extraction and solutionsf all acid soluble constituents, and that the combined solution and sulfid'ation accordingly y not be completed at the same time. The nature'o! the ore may make it advis- "able to continue the action of the acid for some time utter the completion of the sulfiof the soluble in fld, inorder to complete or to increase the extraction of the acid soluble constituents. a

In treating copper sulfid ores containing iron pyrites or in'treating. mixe cop er and iron su 6d ones such as ch copyr zte,

with which iron sulfid is usually present, the ore may with advantage be first sub- ]ected to a preliminary roast at a suitable temperature to decompose the iron sulfid. The roasting may be conducted under con ditions to prevent roasting of the copper sulfid although the sulfid may be oxidized to agreater or less vextent. More or less silver, lead, zlnc, etc., may also be present. The OIe'lS next treated with ,a soluble sul- 'dation,or in the resents of a small assess fid ,such as hydrogen sulfid together with dilute sulfuric acid or other suitable acid in amount and of a strength suflicient to dissolve the iron and other constituents forming acid soluble sulfids; while the oxidized and dissolvedcopper will be sulfidized because of the insolubilitv of the copper sulfid in acids. This sulfidation, and the solution of the soluble constituents, will.

take place simultaneously.

With copper ores which are already in an oxidized state, such as theoxid or carbonate ores, the ores can be treated directly, in the form of theore pulp or slimes or insuspension, with the soluble sulfid and the acid in suitable amount and of suitable strength, so that the formation of the copper sulfid and other acid insoluble sulfids, and the solution of the acid soluble constituents forming acid soluble sulfids, will take place at ,the same time, although as indicated above, the sulfitlation may be complete before the solution, or may continue even after ployed.

After the sulfidation and sollition reactionsare completed, the oreis thensubjected 13o I the solution, depending vupon the relative amounts and strengths of, thereagpnts em- --then subjecting effected by aeration and troth.

The flotation an equilibrium is to flotation to efi'ect the removal. of the The flotation treatment may be an flotation, or it may be a flotation tori'nation oil froth without the use of oil, etc. treatment results in separation of theslllthis so that the remaining ore pu lp'cmitain's the gangue together constituents. Thus, upon subjecting the treated lead-zinc ores to flotation, the lead sulfid, or the partially sulfidized lead particles, will be removed, while the dissolved zinc will remain in solution in the ore pulp. Before the flotation, the excess acid present may be partially neutralized, where the flotation treatment is of such a nature that an excess of acid would be prejudicial.

After the flotation treatment, and the separation of the sulfids, the dissolved metals can be similarly separated from the gaugue by a flotation treatment by first converting them into sulfids after neutralization of the excess acid. Thus ore pul 5 containing zinc in solution may be treate with an alkaline sulfid or alkaline earth sulfhydrate, or with hydrogen sulfid and a neutralizing agent, to rccipitate the zinc as zinc sulfid. By

the ore to a further flotation treatment the precipitated zincsulfid can be floated off and obtained in a form substantially; free from lead. (4 In'the treatment of pulp containin copper and zinc, temporary re'cipitation of fthe zinc sulfid both .' cs may take p ace, particularly in dilute solutions, but this'can be prevented by using a may further react with and unsulfidized copper to form copper sulfid, the zinc again going into solution. In such cases, and Where a clear separation is not directly obtained, it'm'ay be advisable to continue the process until reached so that the soluble constituents-may be dissolved and the insoluble sulfids may be produced.

In treating ores containing-nickel. and copper, together with other ore constituents, the nickel can be dissolved without 'd'is solving the copper, or any dissolved copper can be precipitated without precipitating the nickel as sulfid; After removal of the cop per by' flotation the nickel can subsequently e precipitated as sulfid by neutralizing the excess acid and by treatment with a soluble sulfid, after which the precipitated nickel sulfid can ,itselfbe recovered by a further flotation treatment,

The soluble sulfid used for the sulfidizing process may be hydrogen sulfid,: or other soluble sulfid which. will react inl 'a similar manners. The alkaline sulfids will, in the presence of an excess of acid, be hydrolized into hydrogen sulfid so that they are the equiyalent' of the hydrogen qsulfid in the acid. Also any pie,

with thedis'solved metal with the sulfid ant acid,

hand, the amount of acid may be formed.

prooedm'e of the present inyention"where sulfhydrate, such as calcium sulfhydrate.

Any excess of the hydrogen sulfid or soluble sulfid, which might be prejudicial to the flotation treatment, should be neutralized before subjecting the ore to such treatment.

The acid used for dissolving the soluble constituents may be sulfuric acid of the strength used (.zommercially for extracting ores, or it may be of sulfur dioxid with sulfur ti ihxid, which, when dissolved in the ore pulp, for-n1. sulfurous, or a mixture of sulfurous and sulfuric, acids. With some ores hydrochloric acid also can be used. The strength and amount of the acid. will. necessarily vary somewhat. with different ores, depending upon the strength and amount.- required for sulfur dioxid or mixtures.

dissolving those metal constituents which form acid soluble sulfids and which it is as sired to retain in solution at the end of the sulfidizing process. Accordingly, it may be advisable to use an acid of somewhat greater strength, 'or in somewhat greater amount, than would otherwise be used for extracting the etc if the sulfidizing agent were not simultaneously used. 011 the other be'less than would be required for extracting the metal values if the sulfid were not alsoused as the reagent, for the reason that theaicid will dissolve only the metal constituents formingacid soluble sulfids,-and not those forming acid insoluble sulfids.

By using sulfur dioxid as the acid, and hydrogen sulfid only will the acid insoluble metal sulfids be precipitated, but colloidal sulfur will also ever, it will eii'ect the desired solution the same as would an excess of sulfuric acid, in order p as the sulfidizmg agent, not

' The sulfur dioxid should, how be used in considerable excess-so that that all the soluble constituents maybe disa i solved and only the acid insoluble sulfids formed.

In my companion application Serial No.

36,698, filed June 28, 1915, I have described and claimed the treatment of non-sulfid ores, either simultaneously or successively, with sulfur dioxid andhydro eri sulfid, in order to effect a sulfidizing o the ore and the formation of colloidal sul fur within the ore pulp. ,In said companion. a'p licati'on'i have also described and claime tional or selective seg egation of con;

the free of the constituents forming sulfids gnkes place. Accordingly, the colloidalsuiar process of said flfim'pqflidnh pliscribed seem from each other by such colloidal sulfur process. The claims of said appliesgi .3 however, limited to a, procedure h i i llgidal sulfur is formed and made use of for ofiectmgfi fi q f tation; Wl'ilf if the present eppili t the claims are draii i'i Qiifliiidfilly to the-1:3 tional or selective seiiiftltiifi; the cm bined action of a soluble smfldcess ofany suitable acid sufficient iii to effect solution of the Solubl metal can:

stituents at the same time that sulfidati cation may, by ro er regfiilzitidfl one by effecting t e com ined sulfidat-ion and sole:

tiori sliijii-i tllmeously thereby, embody the generic features of fioielty of the present in-' ventlon; but the colloidal sfilfurpi'occss spe- 'cifically described and lfiiifid in said companion application is of it mace generic nu tureand is not limited to n fit-attains?one I lectivc separation in its broader aspect: iiill .the' colloidal sulfur process specifically claimed insaid application is distinguished from the fractionalseparation process spe cificully claimed in ,vtli filtit'fit application,

in which sulfuric acid is iiilthe and in which the formation of ail-Initiated -'fur is; not contemplated."

' In my companion application: Serial N0;

60,697 filed November 10, 1915, l have .de-.

and claimed n further men-mass ef-- fecting it fractional separation and concentuitionof ores by,. first, dissolving 'th'hcid c soluble constituents of the ore and thereby ,t separating-the same froni the gnnguc, them- .afterfetfecting afra ction a1"firecipitat on of metal constituents forming acid insoluble sulfids from those forming acid soluble 5111- fids by treatment withihydrogen s'ulfid in the presence of a suitablc excess of acid, and finally subjecting the resulting'mixtnre toa flotation treatment. process the solution of themetal constituents precedes the sulfidation treatment so that According to such motel constituents forming acid insoluble sulfide will also be first dissolved if they are- I Qresent in an acid solubl-c'torm, The'pr ocessof the present-invention ,is distingu shed irom such process by the fact-that tho/solu- 'tion and sulfidation' tultehpla oesimultzuie -v ously, instead of successively, so that metal; constituents forming acid insoluble sulfids' are'produced directly without solution, ex oopt perhaps tom )orary' or tra i'sitorx v solution, while the soluble constituents are dis-Q solved in the-presence of thesulfid which" will not "convert thefn into an acid i'nsolublcf. 'form,

"j 'f'. The method ofthc present-invention is distinguished from profiosals heretofore- Inside to c-il'oct afractiohal scpai'iititijl of oxidizcd orcsby 'trcating withfsulfits in the acid insoluble v ment of I cut invention for thereasonrthut the-constititcadilydissolted and for thefuirtherreaso 'that'the constituents f0 7 mg acid insoluble 1 the oxidized. ores-which, a'y' be presence of acids which will prevent certain oxldized' constituents from being sulfidizcd, by the fact that the acid is used, not in small arnounts which \i'ill leave the soluble constitu'ents resent in the pulp in the form of their 031 s, but in amounts suflicient to effect solution of these-soluble oxidized conti'tiientsso that they are physically sopmd from the gangue and from the sulfit cles. The particles whicharc phy i ally separated \villof course 150- lie dissolved, but the solution of the particles still mixed ith n :ulhcring m particles of gangijc or Fai'ticlcs containing constituents'which will sulhdmed; results in removing-the soluble constituents and therebj e'ficct-ing a clcau'cr and morocomfilm fictional separatiim, ln-othor words,

uents,'\' 'hich il not. sulfidlzcin the prosonce or acids pros-cut in the ore pulp ill-2111' oxid 'aIICl IIOD-Gll LKULl com'lition, thc process of present invention contemplates the solfitidi'i- (if-these coustitucnts so that they are piil'lt) fit the end of the flotation treatment -in a dissoliccl otiditiominstead (if lemin r certain oxidized cm1stit-",-

vThe flotation .fieatnwlit,-as' already indi outed, may he efiected by aeration, with agitfl$ll amount of oil can j-be beaten into-the tation, and resulting froth formation, or a.

. 9 M. piilfitdgcther with the on and it froth thus Th Edict-case; the,flotiitionis unta-idly improved-bytlac otthe precipitated sulfids iwhtich are of a more :01" less colloidal nature than the naturally occurring -sulhd constituents of the ore.

the above w'ilhbe' noted thdt the invention is j at more .o'r-less generalapplication, both to the- 't'reattnent'ot completely ox'idi'z stituonts I forming acid insoluble sulfide solution of metalconstituents forming soluble shlfids and the subsequent rein of the sulfids' formed-1b a ifiotationa'trea ment. "The tncatment of oxid ores, howei teiis of purticnln rvalue according to. theprcs ucnts formingacid 1 soluble. sulfide .are'mo ioo sulfids arefconverted;supesfici'allir or cornder} conditions which =mnkei1ioif o cleaner an inore complete fractional separation; Fur thermore,' the production 1 otthe i' sulfide i the presence of the. excess :of acid, tilltljf l" 'ne' r or transitorilyii dissolved during stllfida tion, "gives a; s'ulfid which" is readily" separated by: flotation t eatment; In the use nicnt of 031d 5 n in-f the "tree 105 s ores-,nndto thetlfoate I artially oxidized ores-for eyento some 5111' d ores. I'n all 'cases-fltheproo'od' involves the simultaneous sulfidation of concentration necessary traction of such b texture with the sulfidution, and for the furores readily dissolve ther reason that oxid in it as do also partially rousted or completely roasted ores which frequently con taln considerable mnounts of sulfates and 10 which thus promote the action oi the sulfuric acid in dissolving the soluble coustitucuts. The sulfuric acid can also be readily obtained froi'n smelter fumes by oxidation umounts and so that it can be produced in for commcrclel oper ations, from the sulfid ores themselves.

I claim: ll The method of concentrating ores and l I I o r oi effecting the separation of metal (I()ll-Sll1l1llcuts forming; acid soluble and acid insoluole sulfide from each other, which comprises subjecting the ores containing such (tfillStltlF cuts to the simultuneoi-is action oi hydrogen sulfid and of an acid in suliicicnt amount to efiect'solution of the acid soluble constituents forming acid soluble sulfids. and there by effecting the fractional solution and ex traction of such soluble constituents and the conversion of the i-onstituents forming acid insoluble sullids into sulfiifls, and finuily subjecting the resulting mixture too notation trenltment and thereby separating the insoluble sulfids from the ore pulp; substantially as described.

2. The method of concentrating ores end of effecting the separation of metal constituents forming acid soluble and acid insoluble sulfids from each other, which comprises subjecting the ores containing sucli-u-onstituents to the simultaneous action of hydrogen sulfid and of an acid in suliicient amount to effect solution of the acid soluble constituents forming acid soluble sulfide, and there by. efiecting the fractional solution and exsoluble constituents :i'nd the conversion of the constituents forming acid insoluble sulfide into sul'fids, subjectingthe resulting mixture to a. flotation treatment [and thereby se nirating the insoluble sulfides from the ore pulp, subsequently precipitating as sulfide the dissolved metal constitucuts by neutralizing the excess acid and treating With e suitable sulfid, and finally subjecting the mixture to a further flotation treatment-and thereby separating the pre cipitated sulfids from the ore pulp; substantially as described'. V

3. The method of concentrating non-sulfid copper ores and of efiecting the separation of copper from metals forming acid soluble sulfids, which comprises subjecting the orcs to the simultaneous action of hydrogen sulfid and, of an acid in sufficient amount to effect solution of the acid soluble constituents ldii'ning acid soluble sulfids, and thercby cfl'octil'ig the fractional solution and extraction of such soluble constituents and the conversion of the non-sulfid copper constituents into sulficls, and finally subjecting the resulting mixture to u flotation treatment and thereby seperatingthe insoluble copper sulfid from. the ore pulp; substantially as described.

4:. The method of concentrutin zinc ores and oi eliecting the separation o zinc from metal constituents for-min acid insoluble sulfids and from associutec gcugue, which comprises subjecting the ores to the simultaneous action of hydrogen sulfid and 'of an acid in sufiicient amount to effectsolution of the zinc, and thereby effecting the fractional solution and extraction of the zinc and the conversion of the constituents forming acid insoluble sulfids into sulfids, subjecting the resulting mixture to a flotation treatment and thereby separating the insoluble sulfids from the ore pulp subsequently precipitutii'ig the zinc us sulfid by neutralizinq' the excess acid and treating with a suitable sulfid, and finally subjecting the mixture to it furtheri'lotz tion treatment and thereby separating the precipitated zinc sulfid from the ore pulp; substantially as described.

5. The method of COLICBIlt-littlflfi ores contwining iron pyrites and of efi'ecting the separation of metal constituentsforming'ncid insoluble sul lids from the iron pyrites, which comprises subjecting. such ore to a preliminary roast to conyert the iron pyrites into an acid soluble form, subjecting: the roasted ore to the simultaneous action of hydrogen sulficl and oi? on acid in sufficient amount to prevent conversion of the iron into sulfid,-

and thereby effecting the conversion oi": the constituents forming acid soluble sulfids into sullids, and finally subjecting the resulting mixture to u flotation treatment and thereby separating the insoluble sulfids from the ore pulp; substantially as describedv 6. The method of concentrating sulfid,

ores containing lead-and zinc and of efiecting the separation of the lead and zinc from each other, which comprises roosting the ore to convert the zinc into a soluble form subjet-ting the roasted ore to the simultaneous action of hydrogen sulfid and of an acid in suliicient amount, to effect solution of the zinc, and thereby elfectinp; the fructionalf solution andextraction of the zinc and the conversion of the lead into sulfid, subjectingthe resulting mixture to a flotation treat:

ment and thereby separating the lead sulfid and other acid insoluble sulfide from the ore pulp, subsequently precipitating the zinc as sulfid, and again subjecting he mixture to n flotation treatment and thereby separating the precipitated zinc sulfid from the ore pulp; substantially as described.

I 7'. The method of concentrating 01:95

prises subjecting the ores containing such constituents to the simultaneous action of hydrogen sulfid and of sulfuric acid in amount sutlicient to effect solution of the acid soluble constituents forming acid soluble sulfids, and thereby effecting the fractional solution andextraction of such soluhle constituents and the conversion of the constituents forming acid insoluble sulfids into sulfids', and finally subjecting the resuiting mixture to a flotation treatment and thereby separating the insoluble sulfids from the ore pulp; substantially as described.

8. The method of concentrating zinc ores and of effecting the separation of the zinc from metal constituents forming acid insoluble sulfids, which comprises subjecting the ores to the simultaneous action of hydrogen sulfid and of sulfuric acid in suiiicient amount to dissolve the zinc as sulfate and toprevent precipitation of zinc sulfid, and thereby effecting fractional solution and extraction of the zinc and the conversion of the constituents fprming acid insoluble sulfids into sulfids, subjecting the resulting mixture to'afiotation treatment and thereby separating the insoluble sulfids from the orc pulp, subsequently precipitating the zinc as sulfid by'neutralizing the excess sulfuric acid and treating with a suitable sulfid; and finally subjecting the resulting mixtrue to a further flotation treatment and thereby separating the zinc sulfid from the ore pulp; substantially as described:

9. The method or concentrating sulfid ores containing lead and zinc and of effecting the separation of the lead. and zinc from each other, which comprises subjecting the ore to a sulfatizing roast, subjecting the roasted ore to the simultaneous action of hydrogen sulfid and of sulfuric acid in amount sufficient to effect solution of the zinc as sulfate, and thereby efiecting a fractional solution and extractiom of the zinc as zinc sulfate and the conversion of the lead 'into sulfid, and finally subjecting the resulting mixture to a flotation treatment and thereby separating the lead sulfid and other acid insoluble sulfids from the ore pulp; substantially as described. I

10. The method of concentrating sulfid ores containing iron pyrites, and lead, copper and zinc constituents, and of etfecting' the separation of the lead and copper from the-zinc and from the iron pyrites, which comprises subjecting the oreto a prelimi nary roast to convert the iron pyrites 'into an acidsoluble form, subjecting the roasted ore to the simultaneous action of hydrogen sulfid and of a suflicient amount of acid to effect the solution oft-he zinc and iron, and thereby efi'ecting' the fractional solution and extraction of the zincand iron and the conversion of the lead and copper into sulfid s, l

and finally subjecting the resulting mixture to a flotation treatmentand thereby separating the lead and copper sulfids from the ore pulp; substantially as described.

In testimony whereof I aflix my signature.

RAYMOND F. BACON. 

